1. Field of the Invention
The present invention relates to a sound control system, a sound control device, electronic devices which can produce sound providing a surround effect from their speakers, such as radios, and a method for controlling sound.
2. Description of the Related Art
As is well known, to obtain presence in sound in home theater systems, there are a variety of surround sound systems in which a plurality of speakers are connected to a video display device, such as a TV set. Such surround sound systems include the 5.1 channel surround system having a main control unit, five speakers, and one speaker handling low frequencies, known as a sub-woofer. In this 5.1 channel surround system, for example, three speakers and one sub-woofer are separately arranged in front of a listener and two speakers are placed in the rear to provide the most suitable surround sound to the listener.
On the other hand, wireless audio systems that can be placed at any location by users without limitations are also known (refer to, for example, Japanese Unexamined Patent Application Publication No. 2001-359200, in particular, paragraphs 0011 to 0081 and FIGS. 1 to 16). This wireless audio system, for example, has wireless channels between a main unit and dedicated speaker units. Audio data are transmitted between the main unit and the dedicated speaker units through the wireless channels. Thus, wherever the speaker units are placed, a variety of data including volume control data can be easily transmitted to control the speaker units. As a result, when the speaker units are relocated, the burden on the end user is decreased and the speaker units can be more flexibly placed.
This known surround system requires a plurality of dedicated speakers to be placed in a listening room. To provide sounds having a superior surround effect to a listener, these speakers are preferably placed at the corners of the room. The positions are, however, limited due to the connections to the main unit of the surround system. In addition, the plurality of dedicated speakers disadvantageously require their own floor space. In particular, the dedicated speakers cannot be used for other purposes while not used for the surround system. Thus, these speakers are costly due to their limited use.
Additionally, in the audio system disclosed in the above-described Japanese Unexamined Patent Application Publication No. 2001-359200, the main unit and the dedicated speaker units are connected to each other via wireless channels. This allows the speaker units to be placed at desired positions within relatively large ranges. However, like the above-described surround system, the speakers cannot be used for other purposes, thus being costly.